Heat exchanger only using plural plates

Abstract

Plural heat-exchanging plates for forming an evaporator have plural projection ribs. The projection ribs protrude toward outside of each pair of the heat-exchanging plates to form therein refrigerant passages through which refrigerant flows, and to form an air passage between adjacent pairs of the heat-exchanging plates. The projection ribs protrude from flat surfaces of the heat-exchanging plates toward the air passage to disturb a straight flow of air. The projection ribs are provided in each of the heat-exchanging plates to have a protrusion pitch (P1) between adjacent two, and the protrusion pitch is set in a range of 2-20 mm. Further, each of the heat-exchanging plates has a thickness of in a range of 0.1-0.35 mm, and a passage pitch (P2) between the refrigerant passages is in a range of 1.4-3.9 mm. Thus, in the evaporator formed by only using the plural heat-exchanging plates, a sufficient heat-exchanging performance can be obtained.

Description

This application is related to and claims priority from Japanese Patent Applications No. Hei. 11-8146 filed on Jan. 14, 1999, No. Hei. 11-20519 filed on Jan. 28, 1999, and No. Hei. 11-148811 filed on May 27, 1999, the contents of which are hereby incorporated by reference.1. Field of the InventionThe present invention relates to a heat exchanger formed by only using plural plates for defining inside fluid passages through which an inside fluid flows. The heat exchanger is suitably applied to a refrigerant evaporator for a vehicle air conditioner.2. Description of Related ArtIn a conventional refrigerant evaporator for a vehicle air conditioner, a corrugated fin having louvers for increasing heat-transmitting area is disposed between adjacent flat tubes each of which is formed into a hollow shape by connecting a pair of plates facing each other. In this case, when a flow rate of air passing through the corrugated fines becomes high, over-pressure loss may be caused. Therefore, in the...

AI Technical Summary

Benefits of technology

It is an another object of the present invention to provide a heat exchanger formed by only using plural heat-exchanging plates defining plural inside fluid passages, which readily detects an inside fluid leakage between the inside fluid passages.

More preferably, the inside fluid passages are partitioned into a first inside fluid passage group and a second inside fluid passage group in the flow direction of the outside fluid, the heat-exchanging plates have tank portions at an end side in an extending direction of the projection ribs, the tank portions protrude from the flat surfaces to form communication holes, the tank portions are partitioned into a first tank member and a second tank member at an upstream side of the first tank member in the flow direction of the outside fluid. The first tank member communicates with the first inside fluid passage group and the second tank member communicates with the second inside fluid passage group. Further, the first tank member has a dimension in the up-down direction smaller than that of the second tank member. Thus, within the heat exchanger, a downstream flow area is enlarged as compared with an upstream flow area in the flow direction of the outside fluid. Accordingly, when the heat exchanger is used as a refrigerant evaporator so that air passing through the evaporator is cooled, it can effectively prevent condensed water from scattering to a downstream air side from a downstream air end of the evaporator.

Problems solved by technology

In this case, when a flow rate of air passing through the corrugated fines becomes high, over-pressure loss may be caused.

In the recent years, because the louvers is made finer until a processing limit, processing steps become difficult.

Further, because the corrugated fins are assembled between adjacent flat tubes, assembling performance of the refrigerant evaporator is deteriorated.

That is, since a conventional heat exchanger needs corrugated fins, it is difficult to reduce the manufacturing cost and the size of the heat exchanger.

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